abstract |
In accordance with one embodiment of the present disclosure, a heavy oil may be upgraded by a process that may include removing at least a portion of metals from the heavy oil in a hydrodemetalization reaction zone to form a hydrodemetalization reaction effluent, removing at least a portion of metals and at least a portion of nitrogen from the hydrodemetalization reaction effluent in a transition reaction zone to form a transition reaction effluent, removing at least a portion of nitrogen from the transition reaction effluent in a hydrodenitrogenation reaction zone to form a hydrodenitrogenation reaction effluent, and reducing aromatics content in the hydrodenitrogenation reaction effluent in a hydrocracking reaction zone by contacting the hydrodenitrogenation reaction effluent to form an upgraded fuel. |